WASHINGTON (AFP) - A Florida man who was acquitted of murder in the racially charged shooting death of an unarmed black teenager will not face federal hate crime charges, US justice officials said Tuesday.
US Attorney General Eric Holder said that while the killing of Trayvon Martin in February 2012 was a "devastating tragedy", there were insufficient grounds to charge gunman George Zimmerman with violating federal civil rights laws.
Holder said in a statement that "a comprehensive investigation found that the high standard for a federal hate crime prosecution cannot be met under the circumstances here". Martin's killing was the first in a series of high-profile deaths of young black men in recent years, which have sparked a nationwide debate on race in America.
Holder said Martin's "premature death necessitates that we continue the dialogue and be unafraid of confronting the issues and tensions his passing brought to the surface".
"We, as a nation, must take concrete steps to ensure that such incidents do not occur in the future," he said.
Zimmerman, 31, a neighbourhood watch volunteer in Sanford, Florida, fatally shot Martin as the 17-year-old unarmed high school student was walking home with iced tea and candy.
He insisted he had been following Martin on suspicion that the youth was involved in robbery, and that he shot him in an act of self-defense.
Police soon released him, prompting a national outcry that led to a jury trial for second-degree murder and manslaughter in June 2013, which ended with his acquittal a month later.
The Justice Department statement said federal investigators had carried out an exhaustive review of the evidence in the case and examined whether there were grounds to suggest Zimmerman had broken laws which criminalise "willfully causing bodily injury to a person because of that person's actual or perceived race".
"After a thorough and independent investigation into the facts surrounding the shooting, federal investigators determined that there is insufficient evidence to prove beyond a reasonable doubt a violation of these statutes," it said. "Accordingly, the investigation into this incident has been closed."
"Our decision not to pursue federal charges does not condone the shooting that resulted in the death of Trayvon Martin and is based solely on the high legal standard applicable to these cases," said Acting Assistant Attorney General Vanita Gupta of the Civil Rights Division.
Since his acquittal, Zimmerman has had several brushes with the law over incidents involving violence.
He was arrested in January for aggravated assault before being told he would not face prosecution.
In September last year, Zimmerman was back in the headlines after a Florida man called emergency services alleging he had threatened to kill him in a road-rage altercation. The man declined to press charges over the incident.
In 2013, his then-wife Shellie Zimmerman called police, claiming her husband had threatened her and her father with a gun, but she also refrained from pressing charges.
Several months later, Zimmerman was arrested for domestic violence against a girlfriend who later changed her story and withdrew charges.
The Justice Department said it had also examined additional evidence gleaned from Zimmerman's subsequent encounters with Florida law enforcement before deciding to close the federal case against him.